Exciting Nonlinear Modes In Coherent Atomic Media

Since Einstein proposed the stimulated radiation in 1917 and the laser in 1960,the abundant and extensive phenomena and applications in the laser have been discovered,excavated and utilized by scholars.In particular,nonlinear optics in the laser is widely and closely concerned by scholars,and nonlinear optics is a very active research field in nonlinear optics in the process of interaction between light and matter.Although the knowledge of non-resonant interaction between laser field and medium in nonlinear optics has been deepened,and its colorful phenomena and applications have been grasped constantly,the research on the interaction characteristics of laser field and dielectric resonance has never made a breakthrough.It is well known that strong absorption occurs when the laser field and the dielectric resonance,which makes it difficult to obtain a better nonlinear optical effect.However,the discovery of electromagnetic induced transparency(EIT)in the 1990 s solved the problem of the strong absorption of the light field and medium,and opened a new and broad world for the study of weak light nonlinear light.EIT can effectively suppress the resonance absorption of light by the medium,which is of great significance to research and development of nonlinear optics.In this paper,we consider a resonant three-level ? atomic scheme,working in an EIT effect induced by a continuous wave control field.We show that the equations satisfying the envelope of the probe field can be simplified into several different models,such as the classical Kerr nonlinear Schr?dinger equation(NLES),the saturated nonlinear Schr?dinger equation(SNLES),the saturated nonlinear Schr?dinger equation with a far-tuned harmonic laser field,and the nonlinear Schr?dinger equation with a weak magnetic field.In this work,we propose a simple numerical scheme based on the EIT excitation of rogue waves,which can also to excite breathers and solitons.In this scheme,rogue waves of several nonlinear Schr?dinger equations can be generated by different initial Gaussian pulses.In addition,the region of existence of the excited rogue waves,breathers,and soliton is also shown in this paper,and the initial pulse amplitude and width dependence diagram is obtained.We also obtain the functional relation of the initial pulsed amplitude and background.In addition,compared with previous studies,we not only numerically simulated rogue waves in integrable systems,but also proposed a scheme to generate and control rogue waves in non-integrable systems.This scheme also provides a simple and universal scheme for experimental excitation of various nonlinear modes.At the same time,this method also provides a new idea to suppress the generation of rogue waves in the ocean,that is,we can suppress the generation of rogue waves by changing the amplitude and width of the ocean waves,thereby avoiding the devastating disasters caused by rogue waves.